Objective: To estimate the US prevalence of diabetic retinopathy (DR) among persons with type 1 diabetes mellitus (DM).
Methods: Prevalence data from the New Jersey 725 and Wisconsin Epidemiologic Study of Diabetic Retinopathy were used to estimate the prevalence of DR by age, gender, and race among persons 18 years and older having type 1 DM diagnosed before age 30 years. Severity of DR was determined via masked grading of 7-field stereoscopic fundus photographs. Any DR was defined as retinopathy severity level of 14 or more; and vision-threatening retinopathy, as retinopathy severity level of 50 or more, the presence of clinically significant macular edema, or both. The estimates of the prevalence of DR among persons with type 1 DM were applied to the estimated number of persons with type 1 DM diagnosed before age 30 years in the 2000 US population to obtain prevalence estimates of DR due to type 1 DM in the general population.
Results: Among 209 million Americans 18 years and older, an estimated 889 000 have type 1 DM diagnosed before age 30 years. Among persons with type 1 DM, the crude prevalences of DR of any level (74.9% vs 82.3% in black and white persons, respectively) and of vision-threatening retinopathy (30.0% vs 32.2%, respectively) are high. The prevalence of DR due to type 1 DM diagnosed before age 30 years in the general population 18 years and older is estimated at 767 000 persons having DR of any level (0.37%), and 376 000 persons having vision-threatening retinopathy (0.18%).
Conclusion: Retinopathy due to type 1 DM is an important public health problem in the United States, affecting 1 per 300 persons 18 years and older, and 1 per 600 persons with advanced, vision-threatening retinopathy.